Obstructive Sleep Apnea Syndrome Syndrome (OSAS) is a serious medical condition that is difficult to treat easily and effectively. The condition is marked by a partial or complete closure of the upper airway during sleep.
There are four basic therapeutic modalities in the treatment of OSAS: pneumatic splinting of the airway with positive airway pressure (PAP), airway orthotic (AO) which mechanically dilates the upper airway, surgery, and combination therapy which uses an airway orthotic plus positive airway pressure.
PAP acts as a pneumatic splint which literally blows open the upper airway during sleep such that the tendency for the upper airway to collapse is either eliminated or reduced.
There are a variety of surgeries to treat OSAS, some approaches work better than others. Since this is not the subject of this patent, nothing further will be said on this issue.
Combination therapy typically utilizes mechanical or physical tissue manipulation of the muscles of the upper airway via use of an AO plus pneumatic splinting of the airway. Alternatively, combination therapy may use an AO without mechanical dilation of the upper airway. When an AO is used without mechanical dilation of the upper airway, the AO may be utilized to stabilize an application device for delivery of PAP with a non-claustrophobic interface and the active treatment then depends solely on pneumatic splinting of the upper airway.
Standard PAP therapy usually includes a nasal application device for delivery of the positive airway pressure to the patient's nasal passages. There are different styles of nasal application devices. These include:                a) Triangular-shaped nasal masks which form a seal surrounding the patient's nose on his facial surface,        b) Full-face masks that form a seal on the patient's face around both the nose and mouth,        c) Nasal inserts commonly referred to as nasal pillows.        
The nasal application device is connected to a Continuous Positive Airway Pressure machine (CPAP) via tubing. These air pressure machines (CPAP) can be set to certain and particular pressure settings. Each patient will have a certain and particular pressure level of PAP that will dilate and pneumatically splint his upper airway. When utilized properly, this therapy is very effective in treating the patient with a nocturnally obstructed airway.
Nasal CPAP is considered to be the gold standard in treatment of moderate to severe OSAS. However, this life saving therapy is fraught with significant compliance problems. Clinical studies indicate that compliance on nasal CPAP is less than 50%. Reasons for this non-compliance are numerous and include problems with mask fit and resultant mask discomfort, mask leakage of PAP, claustrophobia, head gear discomfort, head strap discomfort, sleep position (supine) confinement, mouth venting or leakage, chin strap confinement and discomfort, dermatitis, swallowing of air, pressure-related tolerance issues etc.
Airway Orthotics (AO) are oral appliances that are worn in the mouth at night for the purpose of treating OSAS. Historically, there are two basic types of airway orthotics: the tongue retention device (TRD) and the mandibular advancement device (MAD). For the purposes of this disclosure nothing more will be said about the TRD other than to note its existence.
Most mandibular advancement (MADs) devices mechanically dilate the upper airway by moving the lower jaw, or mandible, forward in controlled increments. The airway is dilated by a combination of: pulling the tongue base anteriorly away from the airway and holding it forward during sleep, tightening of the apneic patient's upper airway via anterior and superior movement of the hyoid bone which stretches the infrahyoid muscles attached to the upper airway, innervation of key airway muscle groups such as the genioglossus, palatoglossus, and inferior bellies of the lateral pterygoid(s), and lateral stretching of the hypopharynx.
Mandibular advancement devices can either be fixed or adjustable. In general, adjustable MADs are preferred by most clinicians who treat OSAS because they may be titrated, or gradually adjusted, according to the patient's airway needs. These MAD devices incorporate a variety of different designs and schemes to move the lower jaw forward.
However, advancing of the mandible can result in unpredictable occlusal (bite) changes. Therefore, the clinician must weigh all possible outcome factors, both positive and negative, in formulating his treatment plan.
Mandibular advancing devices, while often helpful, can complicate issues for the patient undergoing “combination therapy.” Complicating issues can compromise the effectiveness of the therapy by resulting in decreased compliance or utilization. Therefore, there is a need to create simple and effective therapies for OSAS that minimize complications. Often, the effectiveness of nasal CPAP, airway orthotics, or combination therapy relates to patient compliance with the therapy. Simpler, less burdensome therapies will generally lead to higher compliance and resultant efficacy in treatment.